1. Field of the Invention
The present invention relates to a data recording and reproducing device to which a scanning probe microscope is applied and a technology effectively used for a data recording and reproducing device having a phase-change type film as a recording medium.
2. Description of the Related Art
At present, a scanning probe microscope which performs observation with a probe being close to the surface of a sample allows the surface of a material to be observed in nano-order of magnitude. Further, by manipulating an individual atom using the scanning probe microscope to form a mark in nano-order of magnitude on the surface of a substance, it is possible to record data with a very high recording density.
On the other hand, at present, many phase-change type recording media such as a recording type DVD (digital versatile disk) and a recording disk for recording and reproducing using a blue or violet laser are used. For this reason, research and development of these recoding media is progressing greatly.
In view of this, the inventors of this invention have examined if or not data can be recorded/reproduced on the recording film using a scanning probe microscope. This is because they thought that since various kinds of researches and developments of the phase-change type recording film are being pursued, the phase-change type recording films with high accuracy and various properties can be relatively easily obtained.
Among the data recording and reproducing devices to which the scanning probe microscope is applied, an exemplary technique using the phase-change type recording film as a recording medium was an optical recording and reproducing device disclosed in JP-A-2001-184751. This optical recording and reproducing device performs data recording using the near-field light when laser light is discharged from a minute aperture having a size smaller than its wavelength. Namely, the data recording is carried out through phase-change by a minute spot in such a manner that the laser output with the minute spot exceeding the resolution of light is given onto the recording film using the near-field light. The data reproducing is carried out, using the fact that the surface potential of the recording film varies attendantly on the phase-change, in such a manner that the surface potential of the recording film is detected by the method using the scanning probe microscope.